Delving into the hyper-stylized world of feuding high school gangs, Crows Zero actually takes place before the events of the manga (hence the title), setting up the origins and rivalries of the iconic characters. Other than the avid fanbase that already exists for the manga, Crows Zero gets some extra box office pull with the casting of heartthrobs Oguri Shun (Kisaragi) and Yamada Takayuki (Train Man) as the lead delinquents. Oguri, who also featured in Miike's Sukiyaki Western Django, continues to impress as one of Japanese cinema's most talented young stars, while Yamada Takayuki leaves behind the sensitive romantic lead image he's cultivated from numerous tearjerkers for a hard-hitting bout in the ring. Rounding out the film's problem teenager cast are Yabe Kyousuke (Dead or Alive, Kids Return), Kuroki Meisa (Under the Same Moon), and Izaki Yusuke and Izaki Hisato from boy band Flame.

Takaya Genji (Oguri Shun) just transferred to Suzuran, a high school notorious for its gang violence. At Suzuran High, hallways are battle zones, bloody brawls are everyday occurrences, and student life is dominated by the political winds of the school's many factions. Genji didn't end up here by accident though. He's here to do what even his yakuza father (Kishitani Goro) couldn't accomplish years before - rule the school. Already stirring up a storm on the first day, Genji is determined to fight his way up the pecking order and unite the gangs. But not if alpha crow Serizawa Tamao (Yamada Takayuki) has anything to say about it.